1. Field of the Invention
This invention is generally related to providing a mechanism for converting the transaction processing protocols between a distributed network using a UNIX system (UNIX is a registered trademark of AT&T), such as the AIX operating system (AIX is a trademark of IBM Corp.), and a distributed system using a Systems Network Architecture (SNA) environment. These networks may include a plurality of interconnected computer workstations, such as the RISC/System 6000, manufactured by IBM Corp. (RISC/System 6000 is a trademark of IBM Corp.), or other similar data processing systems.
2. Description of Related Art
Co-pending U.S. patent application "Transaction Processing Facility within an Operating System Environment," assigned to the assignee of the present invention filed Aug. 17, 1989, Ser. No. 07/395,249, which relates to transaction processing system enhancements to an operating system, is hereby incorporated by reference.
Co-pending U.S. patent application "Communication Interface in a Transaction Processing Environment," assigned to the assignee of the present invention, filed Jun. 29, 1990, Ser. No. 07/546,495, relating to communication services within a transaction processing environment is hereby incorporated by reference.
Conventional transaction processing systems provide a user with distributed processing in a homogenous environment, i.e. transaction processing occurs only within the AIX environment, or the SNA environment. Current standards do not address the issues of interconnectabilty of systems having different transaction processing protocols, or the situation where different transaction protocols may exist within a specific distributed transaction processing environment.
The AIX distributed transaction processing system conforms to the X/Open Portability Guide proposal that specifies implementation of a Two Phase Commit/Presumed Abort (2PC/PA) Protocol. Alternately, the IBM SNA Syncpoint facility is an IBM standard for a distributed transaction processing environment that specifies implementation of a Two Phase Commit/Presume Nothing (2PC/PN) Protocol. Additionally, the protocols differ in the mechanism for identifying the operations that mark the actions which are to be treated as a group, and the mechanism for recovering from failure within the distributed environment.
Therefore, it can be seen that a protocol conversion problem exists when the two networks are interconnected in a transaction processing environment, i.e. the coordination of a transaction across resources in both the AIX network and the SNA network. Traditional solutions to this problem include: (1) restricting transactional operations to a homogenous transaction environment, i.e limiting transaction processing to either the AIX or SNA network; (2) defining a standard, such as the International Standards Organization Transaction Processing Facility (ISO/TP) and map the transaction processing within the non-compatible networks to that standard, i.e. map SNA and AIX to ISO/TP; and (3) providing only limited shared access between the two non-compatible networks, i.e. provide a communications converter between AIX and SNA, but no Two Phase Commit.
In view of the problems associated with prior art protocol conversion techniques, it would be desirable to have a mechanism which would provide the users of either the AIX, or SNA system with a transparent connection to the other distributed transaction processing environment. Further, a mechanism which provides for transforming the necessary protocol and data between AIX and SNA transactional environments, without the necessity of modifying the actual AIX or SNA facility would be advantageous.